Hello all, It was suggested by the guy who had my 400 motor rebuilt that I now (after 3k miles and one oil change) switch to Synthetic oil. I've never used Synthetic and am unsure if its the correct move for an older motor. Any suggestions? Thank you! Vito
Ask about oil on virtually any car website and you’ll get more opinions/advice than you can read. BUT, on THIS website, we can all agree that flat tappet cammed engines need zinc. I use Valvoline VR-1.
This is what I use in my engine, https://www.drivenracingoil.com/hr4-10w-30-synthetic-hot-rod-oil.html
Vito, I grew up driving and maintaining these cars back in the 60's and 70's; we used name brand conventional motor oils and changed frequently at 3000 miles with no major issues. Today, all oils are much improved with the exception of reduced/eliminated zink additive needed on flat tappet engines. We can safely interchange conventional and synthetic oil in our cars without issue; I think synthetic is preferred but generally more pricey. I typically dive my Buick 500-1000 miles a year and I prefer to change my conventional oil out yearly with a filter and keep it looking clean and adding in a bottle of ZDDP additive. If your driving your car in an aggressive manner in hot temps; I think there is a lot to be said for upgrading to synthetic; its really a matter of economics and preference. Hope this helps you in your decision.
Name an engine oil that doesn't have any zinc. https://en.wikipedia.org/wiki/Zinc_dithiophosphate It is NOT just a matter of "zinc". .Zinc, by itself, means nothing. It's the high-pressure anti-wear zinc/phosphorous compound Zinc dialkyldithiophosphates commonly known as ZDDP, that matters. Given stock (weak) valve springs, it doesn't take that much ZDDP to keep a cam and lifters alive. And, while ZDDP was "big news" twenty years ago, half of the actual problem was the infestation of crappy cam cores and junk Chinese lifters--but the Evil EPA got the blame because they forced the oil companies to reduce (not eliminate) the amount of ZDDP in typical motor oil. As long as the oil got the blame, the folks in the cam and lifter business could avoid the warranty cost associated with selling inferior parts.
Just note that even though your motor is brandy new any external oil leaks with a synthetic oil in the motor will give you fits right quick!
Love oil threads....Downunder this is the stuff to use....I keep an eye on prices as it comes up on special quite often. Good ol' school dinosaur oil....Penrite, Aussie oil for Aussie conditions. https://www.penriteoil.com.au/products/hpr-30-20w-60-mineral#/
WITHOUT pissing in anyones cheerios........ I use valvoline syn, 10-30 and add zddp or EOS, which ever I have on hand, and no problems, no need to over think this, zinc ( as its called) was reduced, along with other anti wear additives, I choose NOT to buy over priced exotic oils. at walmart valvoline synthetic - 5 qt is about $20. wix filters or napa, (same thing) $5 or so, ZDDP or EOS actually I use valvoline's synpower oil additive, as I bought couple cases yrs ago, it has all the needed additives (zinc) and moly and boron.
I go with synthetics (often Mobil1 from Wal-e-mart) for all my vehicles and break-in rebuilt engines with conventional oil. VR1 for my last Buick build. I really like synthetics as the parts clean-up so nicely when I'm in there the next time. And there's always a next time.
Oil with stiction eliminator best serves these engines. Hot shot oil blue or black diamond. Put in the Franz oil bypass filter and you will always have an oil supply cleaner than off the shelf.
I forgot to put links in for anyone interested. I just got the transmission fluid from the same company for my 4l80e install. I now have the group IV 5w-40 blue diamond engine oil, transmission fluid, differential oil, and the FR3 additive for the power steering. Im ordering the Franz filter in a couple weeks for micron filtering. #Hotshotssecret. I wish i could get some of this oil for Jim Weise to look at independently. It's a little sciency but good to know and call for clarification. Zinc, yeah! This ain't your fathers's oil.
